Control device of vehicle drive device

Abstract

A control device of a vehicle drive device includes: a hydraulic power transmission device including an input-side rotating element to which power from an engine is input and an output-side rotating element outputting power to drive wheels; a first electric motor directly or indirectly coupled to the input-side rotating element; and a second electric motor directly or indirectly coupled to the drive wheels.

The invention claimed is: 
     
       1. A control device for use in a vehicle having: (i) a hydraulic power transmission device including an input-side rotating element to which power from an engine is input and an output-side rotating element outputting power to drive wheels, (ii) a first electric motor directly or indirectly coupled to the input-side rotating element, and (iii) a second electric motor directly or indirectly coupled to the drive wheels, the control device comprising:
 a processor programed to execute an engine operating point control including:
 a torque of the first electric motor being directly or indirectly adjusted to control an operating point of the engine, and in the control of the operating point of the engine, a torque of the second electric motor being transmitted to the drive wheels; 
 the torque of the first electric motor being adjusted so that a sum of an engine torque and the torque of the first electric motor is equal to an input-side load torque generated in the input-side rotating element depending on a speed ratio of the hydraulic power transmission device; 
 the speed ratio of the hydraulic power transmission device being calculated based on a rotation speed of the input-side rotating element and a rotation speed of the output-side rotating element, the rotation speed of the input-side rotating element being equal to an engine rotation speed indicated by a target engine operating point, and the rotation speed of the output-side rotating element being calculated based on a related value to a vehicle speed; and 
 the input-side load torque being calculated based on the speed ratio of the hydraulic power transmission device and the engine rotation speed indicated by the target engine operating point from a predetermined relationship, and the torque of the first electric motor being determined so that the input-side load torque is equal to a sum of an engine torque indicated by the target engine operating point and the torque of the first electric motor, wherein: 
 the predetermined relationship for calculating the input-side load torque Tp is equation 1:
     Tp=τ×Ne   2   (equation 1)
 
 
 
 
       where τ is a capacitive coefficient that represents the speed ratio of the hydraulic power transmission device, and Ne represents the engine rotation speed. 
     
     
       2. The control device of a vehicle drive device of  claim 1 , wherein
 the vehicle drive device includes an automatic transmission interposed between the output-side rotating element and the drive wheels, and wherein 
 the operating point of the engine is controlled by determining a gear ratio of the automatic transmission and directly or indirectly adjusting the torque of the first electric motor. 
 
     
     
       3. The control device of a vehicle drive device of  claim 2 , wherein
 the gear ratio of the automatic transmission is changed to the side of higher combined transmission efficiency achieved when power from the engine is transmitted through an electric path, through which power transmission is electrically performed by giving and receiving electric power between the first electric motor and the second electric motor, and a mechanical path, through which power transmission is mechanically performed via the hydraulic power transmission device. 
 
     
     
       4. The control device of a vehicle drive device of  claim 2 , wherein
 a determinable gear ratio of the automatic transmission is limited depending on an electric power upper limit value allowed for the first electric motor or the second electric motor. 
 
     
     
       5. The control device of a vehicle drive device of  claim 3 , wherein
 a determinable gear ratio of the automatic transmission is limited depending on an electric power upper limit value allowed for the first electric motor or the second electric motor. 
 
     
     
       6. The control device of a vehicle drive device of  claim 2 , wherein
 the operating point of the engine is controlled so that the operating point of the engine is located along a predetermined operating curve of the engine while a target value of engine output is achieved, and wherein 
 a change to a gear ratio of the automatic transmission causing power circulation in which the first electric motor consumes electric power while the second electric motor generates electricity is restricted. 
 
     
     
       7. The control device of a vehicle drive device of  claim 3 , wherein
 the operating point of the engine is controlled so that the operating point of the engine is located along a predetermined operating curve of the engine while a target value of engine output is achieved, and wherein 
 a change to a gear ratio of the automatic transmission causing power circulation in which the first electric motor consumes electric power while the second electric motor generates electricity is restricted. 
 
     
     
       8. The control device of a vehicle drive device of  claim 4 , wherein
 the operating point of the engine is controlled so that the operating point of the engine is located along a predetermined operating curve of the engine while a target value of engine output is achieved, and wherein 
 a change to a gear ratio of the automatic transmission causing power circulation in which the first electric motor consumes electric power while the second electric motor generates electricity is restricted. 
 
     
     
       9. The control device of a vehicle drive device of  claim 5 , wherein
 the operating point of the engine is controlled so that the operating point of the engine is located along a predetermined operating curve of the engine while a target value of engine output is achieved, and wherein 
 a change to a gear ratio of the automatic transmission causing power circulation in which the first electric motor consumes electric power while the second electric motor generates electricity is restricted. 
 
     
     
       10. The control device of a vehicle drive device of  claim 1 , wherein
 the operating point of the engine is shifted to the side of a larger product of combined transmission efficiency and engine efficiency achieved when power from the engine is transmitted through an electric path, through which power transmission is electrically performed by giving and receiving electric power between the first electric motor and the second electric motor, and a mechanical path, through which power transmission is mechanically performed via the hydraulic power transmission device. 
 
     
     
       11. The control device of a vehicle drive device of  claim 1 , wherein
 the operating point of the engine is shifted to the side of a smaller total loss acquired by summing a power transmission loss and a loss of the engine power generated when power from the engine is transmitted through an electric path, through which power transmission is electrically performed by giving and receiving electric power between the first electric motor and the second electric motor, and a mechanical path, through which power transmission is mechanically performed via the hydraulic power transmission device. 
 
     
     
       12. The control device of a vehicle drive device of  claim 2 , wherein
 the second electric motor is coupled between the output-side rotating element of the hydraulic power transmission device and the automatic transmission. 
 
     
     
       13. The control device of a vehicle drive device of  claim 3 , wherein
 the second electric motor is coupled between the output-side rotating element of the hydraulic power transmission device and the automatic transmission. 
 
     
     
       14. The control device of a vehicle drive device of  claim 4 , wherein
 the second electric motor is coupled between the output-side rotating element of the hydraulic power transmission device and the automatic transmission. 
 
     
     
       15. The control device of a vehicle drive device of  claim 5 , wherein
 the second electric motor is coupled between the output-side rotating element of the hydraulic power transmission device and the automatic transmission. 
 
     
     
       16. The control device of a vehicle drive device of  claim 6 , wherein
 the second electric motor is coupled between the output-side rotating element of the hydraulic power transmission device and the automatic transmission. 
 
     
     
       17. The control device of a vehicle drive device of  claim 7 , wherein
 the second electric motor is coupled between the output-side rotating element of the hydraulic power transmission device and the automatic transmission. 
 
     
     
       18. The control device of a vehicle drive device of  claim 8 , wherein
 the second electric motor is coupled between the output-side rotating element of the hydraulic power transmission device and the automatic transmission. 
 
     
     
       19. The control device of a vehicle drive device of  claim 9 , wherein
 the second electric motor is coupled between the output-side rotating element of the hydraulic power transmission device and the automatic transmission.